display two arrays on uitableview sorted by date - ios

Question

I have two arrays one of which is a tweets array and contains twitter tweets. Another of which is a instapics array and contains Instagram pictures. Both of these Arrays have different keys for date. The twitter one had created_at and the instagram one has created_time. I want to display both of them on a single UITableView and have them organized by date. Here is what I am doing so far, the problem with this however is that it only shows Instagram Pictures:
- (void)sortArrayBasedOndate {
NSDateFormatter *fmtDate = [[NSDateFormatter alloc] init];
[fmtDate setDateFormat:#"yyyy-MM-dd"];
NSDateFormatter *fmtTime = [[NSDateFormatter alloc] init];
[fmtTime setDateFormat:#"HH:mm"];
totalFeed = [totalFeed sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2) {
// Instagram Date Retrieval
NSDictionary *instagram = self.instaPics;
NSString *createdAt = instagram[#"created_time"];
int createdAtN = [createdAt intValue];
NSTimeInterval timestamp = (NSTimeInterval)createdAtN;
NSDate *date1 = [NSDate dateWithTimeIntervalSince1970:timestamp];
// Twitter Date Retrieval
NSDictionary *twitter = self.tweets;
NSString *twitterCreated = twitter[#"created_at"];
int createdAtTwitter = [twitterCreated intValue];
NSTimeInterval timestampTwitter = (NSTimeInterval)createdAtTwitter;
NSDate *date2 = [NSDate dateWithTimeIntervalSince1970:timestampTwitter];
return [date1 compare:date2];
}];
}
The above is how I am trying to organize them on the array, below is how I am attempting to display them:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
id object = [totalFeed objectAtIndex:indexPath.row];
if ([tweets containsObject:object]) {
static NSString *Twitter = #"TweetCell";
UITableViewCell *twitter = [self.tableView dequeueReusableCellWithIdentifier:Twitter];
NSDictionary *totalArray = totalFeed[indexPath.row/2];;
// Creation Code Not shown
return twitter;
}else{
static NSString *Instagram = #"InstagramCell";
UITableViewCell *instagram = [self.tableView dequeueReusableCellWithIdentifier:Instagram];
NSDictionary *entry = instaPics[indexPath.row / 2];
// Creation Code not Shown
return instagram;
}
}

Answer 1

The easiest solution would be if you add a common "creationDate" key to all objects in the
totalFeed array. The value of this key should be an NSDate created from
the "created_at" or "created_time" key.
Then you can just sort the array according to this key:
NSSortDescriptor *sortDesc = [[NSSortDescriptor alloc] initWithKey:#"creationDate" ascending:YES]];
totalFeed = [totalFeed sortedArrayUsingDescriptors:#[sortDesc]];
If you cannot do that for some reason, you have to fix the comparator method, it does
not use the passed arguments obj1, obj2 at all.
Something like (pseudo-code):
totalFeed = [totalFeed sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2) {
NSDate *date1, *date2;
if ("obj1 is a Twitter") {
date1 = "get created_at from twitter obj1"
} else {
date1 = "get created_time from instagram obj1"
}
if ("obj2 is a Twitter") {
date2 = "get created_at from twitter obj2"
} else {
date2 = "get created_time from instagram obj2"
}
return [date1 compare:date2];
}];
In any case, in cellForRowAtIndexPath you have to access totalFeed[indexPath.row]
(without dividing by 2, which does not make sense here).
More sample code:
NSArray *instaPics; // your instagrams
NSArray *tweets; // your tweets
NSMutableArray *totalFeed = [NSMutableArray array]; // the common array
// Date formatter for the tweets. The date format must exactly
// match the format used in the tweets.
NSDateFormatter *fmtDate = [[NSDateFormatter alloc] init];
[fmtDate setDateFormat:#"..."];
// Add all instagrams:
for (NSMutableDictionary *instagram in instaPics) {
NSString *createdAt = instagram[#"created_time"];
NSDate *date = [NSDate dateWithTimeIntervalSince1970:[createdAt doubleValue]];
instagram[#"creationDate"] = date;
[totalFeed addObject:instagram];
}
// Add all tweets:
for (NSMutableDictionary *twitter in tweets) {
NSString *twitterCreated = twitter[#"created_at"];
NSDate *date = [fmtDate dateFromString:twitterCreated];
twitter[#"creationDate"] = date;
[totalFeed addObject:twitter];
}
// Sort
NSSortDescriptor *sortDesc = [[NSSortDescriptor alloc] initWithKey:#"creationDate" ascending:YES];
[totalFeed sortUsingDescriptors:#[sortDesc]];